This invention is directed to check detection device in the neck and finished portions of glass containers especially bottles, cups, etc. in a bottle manufacturing or filling line, and this invention more specifically concerns such a method which is suitable to the automation. Especially, this relates to the check detection device of the neck and finished portions of glass bottles with auto slicing function.
Conventionally, in a bottle manufacturing and filling line, detection of checks in the neck and finished portions of a bottle was primarily carried out in the line by visual inspection, or by setting manually and visually emitters (a) and receivers (b) according to the types of bottles and to the types of check defects on public-known handling machines. The a:b by plural emitters (a) and receivers (b) occupy plural of inspection stations depending on the portion to be inspected.
Further another system which is to emit light by lighting system on the neck and finished portions of a bottle and to extract reflecting light as an electrical signal level by photoelectricity transformation element such as CCD camera, is proposed.
However, in the above conventional visual inspection, it is impossible to detect defects on high speed flowing line. In the inspection method of setting manually and visually plurals of emitters and receivers depending on the types of checks, it is impossible to detect where the defects exist and also, it is impossible to inspect all kinds of checks in neck and finished portions of a bottle. Further, in changing the mould of the bottle, it takes a long time to set emitters, etc.
Further, as the example using the latter inspection method of the above, the inspection system, which was disclosed in the journal of xe2x80x9cPatent disclosure Showa 59-6524 Bi. 3xe2x80x9d, can be pointed out. In this journal, the system is composed of rotating bottles, emitting lights from one emitter on the neck and finished portions, and extracting continuously reflecting lights as a level information by electrical signal from the photoelectricity transformation element such as a CCP camera etc.
Further, as disclosed in the same journal, in this composition, deterioration of emitters due to time lapse, changing of brightness of the circumstance due to time lapse and variation of inspection sensibility of emitters due to change of voltage of the electrical source, will occur. Therefore, in order to protect the above variations, it is organized to control the amplification of process signals in order that the average figures of the process signal levels will come to the certain figures pre-set based on the average level of the process signals.
However, in this composition, it is impossible to elevate the inspection accuracy due to the fact that the standard levels of analog signal levels, which are gained by CCD cameras etc., are altered in response to the change by time lapse. Further, in this conventional inspection system, thought the detection of vertical checks in the neck and finished portions, for example, is comparatively effective, it still has the problem that the detection sensibility is low for the horizontal checks appeared along the screw of a bottle.
Accordingly, in this system, the inspection for all kinds of checks in the neck and finished portions for example are impossible and the problems of necessity of re-setting cameras, lights, sensibility etc. at the time of changing mould, are still there, same as the former visual inspection method.
Now, the inventor of this application developed a check detection device of neck and finished portions of a bottle having 640 multi-detection light channels of the emitters and receivers by setting for example 10 emitters (N=10) and 64 receivers (M=64) with dome shape against the bottle neck and finished portions for example (Nxc3x97M=640 channels). This device is now applying the patent (1996 patent pending No. 255604).
According to the above method, detecting accuracy of defects is improved greatly compared with the conventional system because the data of 640 channels for example can be maintained per one inspection point i.e. one scan by the multi-directional emitting and receiving lights. Further, unexpected detects, which are in what part or to what direction of the neck and finished portions of bottles, the defects will occur, can be detected.
By the way, considering the condition of existing one emitter against M number of receivers for example, in the inspection system which the inventor of this application developed previously, the emitted lights to the neck and finished portions of the inspected bottles from the emitters are reflected and passed through at these portions and are in-put to each receiver of numbers of M which is arranged in each different position.
In this case, if the inspected bottles are good ones, the figures will be under the threshold figures of the differential level figures of the good bottles previously registered. An in case of the rejected bottles, if the angle position of an emitter and a receiver positioned 1:M is proper, in other words, if the defecting light can be received in this position, the differential level figures, which are output in either of receivers of M numbers, exceed the threshold figures and detect defects.
Similarly, in the inspection system having emitters of N numbers and receivers of M numbers which was developed previously by the inventor of this application, the probability of detecting defects by the multi-directional lights will become higher in proportion to the numbers of N and M.
Now, one problem in case of adopting the inspection system mentioned above is that generally a scores of molds for bottle building, exists in bottle manufacturing factories and especially molds of mouth type (angle type) among them are altered in every several days because of mold diminishing, improper building, etc. In other words, building molds are altered every day. At this time, small shape variation due to such a projection, a dent, etc., which is produced by the jointing of molds, will occur.
The second problem is that the position gap of the handling machine which is a rotating means for inspected bottles, will occasionally occur with time lapse due to its mechanical composition.
The third problem is that the phenomenon of eccentricity, position gap, etc. will occur at the time of bottle rotation by the handling machine because the specification of height, outside diameter, inclination, neck bending of bottles after the bottle building, are comparatively rough.
The above-mentioned three problems will actually be an important problem in this kind of inspection system. Especially, at the time of arranging N numbers of emitters and M numbers of receivers in each different position, the above-mentioned shape change, eccentricity, position gap of the inspected bottles will lead to the excluding good bottles, and to lower the yield rate of production greatly due to the multi-directional emitting and receiving lights.
In other words, the action of emitting lights from multi-direction to the neck and finished portions of bottles, and receiving lights multi-directionally, for example, is very effective at the point of elevating the detecting ability for the defects existence and for the defects portions as mentioned above. Further, the more the numbers of emitters and receivers are, the more the detecting ability of defects will be elevated. However, the problem of increase of the possibility of excluding good bottles due to the above three problems is still there.
This invention aims to cope with the 3 peculiar problems mentioned above utilizing the characteristics of an inspection system, which has multi-directional light channels having N numbers of emitters and M numbers of receivers as mentioned above. Further, this invention aims to supply the check detection device of the neck and finished portions of glass bottles which can improve quality control by setting the mould change automatically depending on bottle types which was difficult previously, by overall detecting checks in the neck and finished portions of a glass bottle with no relation to the portion and type of defects, by detecting a bubble, a stone, a chipped and unfilled thread and deformation, and further by assorting defects into both portions and types.
Also, this invention aims to supply the check detection device of the neck and finished portions of glass bottles without lowering defects detection ratio by less adding registration of good bottles and doing automatic registration of good bottles at the initial registration.
In order to achieve the above objects, the present invention is directed to a check detector for the neck and finished portions of a bottle, which comprises:
a rotating means which is capable of rotating an inspection bottle on the inspection position;
a plurality of emitters and a plurality of receivers arranged on an approximately hemispherical fixture surrounding the neck and finished portions of an inspected bottle as a center;
means for obtaining Nxc3x97M data per single scanning to the inspected portion of said inspected bottle mentioned above wherein N is a number of emitters and M is a number of receivers;
means for assorting the data obtained;
means for differentiating the data means for comparison process of threshold figures which is to judge whether the differential output from the above differential means will exceed the fixed threshold figures or not.
means for collecting automatically the data of a good bottle of all or partial channels of Nxc3x97M in each periodic time or in each passing numbers of glass bottles against the threshold figures initially registered and decided as a good bottle; means for enforcing automatic setting process which is to reset new threshold figures by 1) which is produced by adding the certain amount of margin figures on the differential figures of the collected data as the threshold figures, 2) against threshold figures newly set, repeating continuously the action of collecting automatically the data of a good bottle of all or partial channels of Nxc3x97M in each periodic time or in each passing number of glass bottles and adding in order the certain amount of margin figures on the differential figures;
In other words, in this detection device of neck and check portions of glass bottles, inspection bottles are rotated in check position, N numbers of emitters and M numbers of receiver are arranged on the approximately and preferably hemispherical fixture around the neck and finished portions as a center, and then Nxc3x97M numbers of making bright processing is done by the receivers on each inspection point under the constant intervals on all circumference of the neck and finished portions of glass bottles.
The term of xe2x80x9cmaking bright processingxe2x80x9d means obtaining a receiving light. The term xe2x80x9cinspected pointxe2x80x9d means an area where emitting and receiving lights are focused on an inspected bottle per one scan.
At this time, Lxc3x97Nxc3x97M numbers of light process data are collected assuming inspection scans of all circumference of the inspected bottle to be L.
Next, by known assorting method of data, which assort data from each emitter and receiver according to channel units, assorted data can be obtained. This is called data assorting process. Then, differential process of data from receiving light is done according to each Nxc3x97M receiving light in the above L. This differential process means the generally known process of difference and is treated by known differential method. By this differentiating, a changing point of brightness and darkness and changing amount of receiving light are detected;
1) For a good bottle, the judge level of the differential level is automatically set according to Nxc3x97M channels for such a level that any of the amount of change detected in the above does not exceed the threshold data, then a check is not detected.
2) For a defective bottle, a check is detected since some of the differential data of Nxc3x97M channels exceed the judge level of the differential level, and then exclusion signal works and omit this.
The xe2x80x9cjudge level of the differential levelxe2x80x9d means a value, which is differentiated, and a predetermined value with a fixed margin.
In the present invitation, interference between a plurality of emitters and receivers does not occur, since emissions from each emitter are not simultaneous. Thus, detecting checks can be made exactly and with over-lapping.
Similarly, detection of a bubble, a stone, a chipped and unfilled thread and deformation which are known defects in the neck and finished portions of a bottle can be detected, since in the present invention, the reflected light can be detected and changing of the reflected light direction can also be detected. Further, particularly, with respect to finished top surface, of the neck and finished portions, a top surface line over finish, unfilled finish, over press finish and bubble on finish etc., can also be detected.
Further, the check detector of the present invitation is capable of assorting defects into both portions and types, and, therefore, users are capable of improving the quality control and are capable of raising the productivity. Namely, against the Nxc3x97M channels, a user is able to set the type of defects and is then able to read the assorting in each counter.
Further, the initial registration of a good glass bottle is done by the registration of the base patterns of finish, thread, neck and shoulder portions of a glass bottle, and also done by the numbers of 6xcx9c24 which are almost equal to the registration numbers of star wheel sections. Then, on line inspection follows.
Further, known reflected lights on the inspection portion of the inspected items in each Nxc3x97M channel of the good registration are collected around the bottle by the receivers, and new threshold values are set by adding allowance values which are voluntary setting values to the differential values of the above data. In this case, if the above differential values are detected in the range of allowance values, judgement of xe2x80x9cGoodxe2x80x9d is given and if the above differential values are detected out of the allowance value, judgement of xe2x80x9cNo goodxe2x80x9d is given. This procedure is done on all channels of Nxc3x97M and is done on all or part portions of finish, thread, neck and shoulder of a glass bottle and around the bottle, and then, judgment of xe2x80x9cGoodxe2x80x9d or xe2x80x9cNo goodxe2x80x9d for the inspected item is done. In this case, among the above differentiation values if, among channel numbers, the numbers which exceed allowance value, exceed judgment values set up voluntarily, they are judged as xe2x80x9cNo goodxe2x80x9d and excluding signals are emitted. To the contrary, the above channels do not exceed judgement values, they are judged, as xe2x80x9cGoodxe2x80x9d to emit excluding signal.
Now, the inspection process for a bottle represented by a glass bottle is completed and this inspection process is done continuously.
At this time, differential values of Nxc3x97M channels which are judged xe2x80x9cGoodxe2x80x9d are to be remembered, and then, differential values of Nxc3x97M channels of good bottles against each inspection process numbers or each inspection process numbers with periodical intervals pre-set are to be remembered.
Then, according to each channel of Nxc3x97M remembered, the above mentioned threshold value is calculated from either peak value, average value or standard deviation value of good bottles, and this threshold value is re-set. After that, the above treatment is done continuously.
A series of auto setting process of the above is called auto slice. And by this auto slice, variation of moulds, delicate shape change of moulding due to abrasion, variation of the system which holds and rotates bottles in each section of star wheels of handling machines, and variation with time lapse are automatically perceived and sensibility of the inspection can be automatically corrected or set.
Further, this sensibility of the inspection are corrected over all channels of Nxc3x97M but according to the channels, the channels of which inspection sensibility becomes higher or becomes lower, will appear. However, this system will work in harmony with moulding condition and bottle handling condition, and then, proper inspection sensibility of each channel can be kept by lowering of the reject of good bottles.
According to this invention, check detection of neck and finished portions of a glass bottle can be done comprehensively, and troublesome setting of a mould change depending on bottle type can be conducted fast due to fixing of the emitters and receivers arrangement and to automatic setting of the sensibility. At the same time, defects such as a bubble, a stone, a chipped and unfilled thread, deformation etc. in the neck and finish portions of a bottle can be detected, and by assorting defects into both portions and type, quality control improvement can be achieved.
As for the emitters used in the present invention, LED emitters are preferably used because of high-speed emission. However, the type of emitters is not limited and laser beam may be used as the emitter.
As for the receivers used in the present invention, photo receivers are preferably used. However, the type of receiver, which can be used, is not limited and any conventional device for receiving and detecting light may be used so far as the variation of light amount from the emitters can be detected.
The emitters and receivers used in the present invitation can be either fixed or semi-fixed on a fixture, preferably positioned approximately hemispherically around an inspected bottle. The position of the emitters and receivers can be arranged most suitably from time to time against the inspected bottles.
In the present invention, the assorting of the defects to both positions and types can be achieved by the detection of the channel position.
By the inspection device in the present invention, which is constituted of the above, the accuracy of the inspection of the neck and finished portions of a bottle can be improved in the bottle manufacturing factories, and the time of the mould change according to the bottle kinds can greatly be shortened. Further, the analysis and counter measure for the defect causes are taken fast by properly expressing the information of the defect kinds. And then, the increase of the productivity and the promotion of the labor saving can be expected by the above. Furthermore, the shortening of the time of mould change and much saving of the labor of line operators at the on-line operation can be expected. The kinds of defects of the inspected portions can also be detected constantly due to the keeping of the inspection sensibility.